The properties of recycled WC bottle material separated from the post-consumer waste stream were investigated. In the first part of this study, attention was focused on the mechanical properties. In order to examine the effects of recycling, the properties of the recycled material were compared with those of virgin PVC and pure material that had been processed into bottles and then granulated. The effects of pulverization of the recycled material were also studied. The mechanical properties investigated included tensile, fatigue, and environmental stress cracking tests, in conjunction with fracture surface examination, molecular weight determination, and impurity analysis. It was found that the recycled material did show significant reduction in strength and ductility, though pulverization improved the situation considerably. The main reason for this was the presence of impurities, especially PET, which although present at levels below 0.5%, had a large effect on the properties.